Arizona Open Carry Restrictions

How old do you have to be to open carry a fixed blade knife in Arizona?
And what are the restrictions such as blade length and how visible does it have to be
I’ve never heard of a knife license, but I’m 15 and carry a pocket knife almost everywhere with me (minus school of course!) and never have problems. TBH, I don’t see why you’d need to carry around a fixed blade knife. So i just carry around a pocket knife and have had no problems. I don’t think there’s an age limit…but here’s a link that may help…http://www.thebladeshop.com/State_Knife_Laws_s/478.htm
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